School Girl Crushed the first part of the 6th aired and 7th produced episode in season 4 of Dexter's Laboratory, which first aired on May 23, 2003. In this episode, Dexter and Mandark are going head-to-head at a science fair, but a new student named Soyen Chen outperforms the boy geniuses. Dexter and Mandark reluctantly join forces to get rid of her.
At the Huber Elementary Science Fair, several children showcase their science projects. Dexter has a crowd of students gathered around him praising his science project. Mandark has his own crowd of students praising him for his science project. Dexter and Mandark's crowd both start arguing with each other until Mr. Phillips Luzinsky interrupts them. Dexter and Mandark are hoping that one of them will win the award, but things dramatically change when an exchange student named Soyen Chen is crowned the winner of the contest. Dexter and Mandark are oblivious to their loss, and the crowd looks at Soyen and her science project. She introduces her science project and everyone, except for Dexter and Mandark, runs toward her. Soyen crowd surfs out of the school. Mandark and Dexter watch in shock, and Mr. Luzinsky introduces the boys to Soyen, the new student. Mandark and Dexter reluctantly team up to get rid of Soyen.
Later, Dexter and Mandark go to their labs and construct weapons while they talk about each other behind their backs. Soyen is walking down the street and Mandark targets her with his tank's laser. Mandark brags about his intellect, ignoring Soyen. Dexter rams his tank into Mandark's, causing both him and the tank to wobble. Mandark puts his tank in reverse and steamrolls Dexter's tank, but ends up falling into a lake. An argument between them ensues all day and well into the night. Soyen walks by telling them that there was a math test at school. She shows them her grade, and Dexter and Mandark team up again.